Rockwell Automation 1398-DDM-xxx ULTRA 100 Series Drives Installation Manual - Manual (Page 279)

Publication 1398-5.2 – PDF 1997
Electromagnetic Compatibility Guidelines for Machine Design E-6
The primary objective of a high frequency ground system is to provide
a well defined path for HF currents and to minimize the loop area of
the HF current paths. It is also important to separate HF grounds from
sensitive circuit grounds. “Single Point Ground Types” shows single
point grounds for both series (daisy chain) and parallel (separate)
connections. A single point, parallel connected ground system is
recommended.
A ground bus bar or plane should be used as the “single point” where
circuits are grounded. This will minimize common (ground)
impedance noise coupling. The ground bus bar (GBB) should be
connected to the AC ground, and if necessary, to the enclosure. All
circuits or subsystems should be connected to the GBB by separate
connections. These connections should be as short as possible, and
straps should be used when possible. The motor ground conductor
must return to the ground terminal on the drive, not the GBB.
Figure E.3 Single Point Ground Types
Intro
CIRCUIT
1
CIRCUIT
2
CIRCUIT
3
CIRCUIT
1
CIRCUIT
2
CIRCUIT
3
PARALLEL CONNECTION SERIES CONNECTION
Ground Bus Bar